Ink jet printing systems are known in which a print head defines one or more rows of orifices which receive an electrically conductive recording fluid, such as for instance a water base ink, from a pressurized fluid supply manifold and eject the fluid in rows of parallel streams. Printers using such print heads accomplish graphic reproduction by selectively charging and deflecting the drops in each of the streams and depositing at least some of the drops on a print receiving medium, while others of the drops strike a drop catcher device.
An existing assembly method for assembling the components of an ink jet printhead includes locating the droplet generator with the aid of an assembly fixture, then using an epoxy or other adhesive to fasten it into place. The charge plate/catcher assembly was then aligned to the droplet generator through the use of external adjustment fixtures. Once a proper alignment was achieved, the charge plate/catcher assembly was fastened with screws to the common frame holding the droplet generator.
Unfortunately, existing assembly and alignment methods have several problems. For instance, the use of adhesive increases assembly cycle time, since it takes several hours for the adhesive to cure. The use of epoxy is also problematic in that epoxy is temperature and humidity sensitive. Finally, the sensitivity of the alignment is such that the final fastening of charge plate/catcher assembly once alignment is achieved can and does alter the alignment, requiring a realignment. It is seen then that there is a need for an apparatus for mounting and alignment components of an ink jet printhead which overcomes the problems associated with existing techniques.